Power distribution boxes (PDBS) are commonly used in automotive vehicles to simplify electrical system wiring by eliminating multi-branch wiring and consolidating fuses, relays, and other electrical components in a single location. A PDB typically comprises a housing having a plurality of integrally formed external receptacles for receiving electrical connectors, fuses, relays, and other components. The electrical connectors which plug into the receptacles terminate wire harnesses which extend from the PDB to connect with various electrical systems throughout the vehicle. Terminals on the ends of the wires making up a wire harness are held in internal chambers formed in the electrical connector so as to make electrical contact with mating terminals within the PDB when the connector is inserted into its receptacle.
It is known to fasten a cover over the otherwise open top surface of the connector which receives the terminals, the cover serving to prevent the terminals from inadvertently being dislodged from their respective chambers by vibration or by tension on the wires. The cover also serves to prevent a tool used to bolt the connector to the receptacle, such as an air ratchet, from inadvertently becoming entangled in the wires and damaging the wires. Such a cover is indicated by reference numeral 10 in FIG. 1, the cover shown operatively attached to an electrical connector 12. Terminals (not shown) are crimped to the ends of wires 16 and are retained in chambers 18 extending through the connector, the wires being forced to make a right-angled bend and extend horizontally out the open end of cover 10 when the cover is snapped into engagement with the connector.
In some automotive PDB installations, space constraints and electrical system requirements result in a wiring layout wherein the bundled wires of a wiring harness extend from an electrical connector mated with a receptacle on a first surface of the PDB and must then make a sharp turn around the edge or corner of the PDB to be routed along a second surface of the PDB. It is known to use a clip 16, as shown in FIG. 2, to secure the wires to the second surface of the PDB along which they extend. The wires (not shown) are routed to lie in the concave side of a trough 22 which extends along clip 16 and are secured therein by wrapping tape (not shown) around the trough and wires. The back side of clip 16 lies against the second surface of the PDB and is connected thereto by means of slots 19 and detent tabs 20 which engage mating means on the PDB.
It has been found that during operation of an automotive vehicle, engine vibrations are transmitted through the wires of the wiring harness and sometimes cause mechanical failure of the wires or the joints between the wires and their respective terminals within the electrical connector. While the prior art connector cover 10 discussed hereinabove prevents the wires and attached terminals from being dislodged from the electrical connector, it does not adequately restrain the wires against vibration parallel to the surface of the cover and perpendicular to the axes of the terminals. Neither does the wire clip 16 discussed hereinabove effectively suppress this mode of vibration, which is believed to cause failure of the wires at or near the wire/terminal interface.
Even when the prior art connector cover and wire guide clip are used in combination, the portions of the wire harness extending between the connector cover and the wire guide clip are exposed and so are prone to being damaged or contaminated in that area.